In subsea applications, for example subsea oil production, data communication demand is increasing for controlling and monitoring subsea equipment. The increasing data communication demand may be met by fiber-optical data communication.
For this purpose fiber optical cables of umbilicals are for example terminated by fiber optical terminations in umbilical termination heads located in a subsea environment.
Common fiber optical terminations include a tubular-shaped optical fiber termination unit receiving an optical cable from the umbilical and a plurality of hoses from the fiber optical termination unit to a plurality of optical connectors. The hoses fulfill the purpose of pressure compensating the oil filled side of the fiber optical termination. Due to this, a certain length of the hoses of 1-3 meters is required to compensate both the hoses and the dead volume in the fiber optical termination. However, limited space inside the umbilical termination heads for said hoses makes the installation of a fiber optical termination inside an umbilical termination head difficult and time consuming. This increases the risk of failure in the optical fibers due to bending. Further, hydrogen gas produced by zinc bars for cathodic corrosion protection can diffuse through the hoses and lead to physical degradation of the optical fiber, in particular to fiber darkening, and thereby the signal reading can be distorted and the system can possibly be rendered inoperable due to the optical loss budget being exceeded.